Heretofore, polycrystalline Ni-Zn ferrite, Mn-Zn ferrite, single-crystal Mn-Zn ferrite or high-hardness permalloy, have been used as a material for magnetic head-sliders for magnetic recording and/or reproduction.
The recent tendency is towards a higher recording density and higher wear resistance of the head slider material and, for this reason, a thin film magnetic head is being used in an increasing volume. In keeping up with acceptance of the thin film magnetic head, an optimum material which will satisfy the properties required of each of the magnetic circuit members for magnetic recording and/or reproduction and the wear-resistant slider has been under development as a material for magnetic circuit members or as a slider material.
Thus thin films of permalloy, sendust or amorphous metal having superior magnetic properties in the high frequency range are preferentially employed as a material for magnetic circuit members. On the other hand, alumina based materials are thought to be desirable as a material for functional members for which high wear resistance is required.
For the wear resistant material for sliding members, which is a nonmagnetic material, precision machinability, machining efficiency, high strength, dense structure, affinity (or compatibility) with the recording medium, lubricity and thermal matching properties with respect to thin metal films, have been required besides the wear resistance.